Amtrol ST-1 Therm-X-Trol Thermal Water Heater Expansion Tank For Tankless Water Heaters (Stainless Waterway)

Amtrol invented the thermal expansion tank to control pressure build-up in closed, potable water systems. This prevents the water heater pressure relief valve from opening, saves energy and eliminates a potential safety hazard. All Therm-X-Trol expansion tanks are made in our ISO 9001:2015 certified facility

Features

• Accepts expanded water as system temperature rises and returns hot water to system when demand occurs.
• Patented air cell eliminates pressure surge to protect heat exchanger.
• Required by most building codes and all water heater warranties.
• 7-Year limited warranty: The industry's longest.
• 304L stainless steel waterway
• Big protection in a compact size.